Flange height and lip accuracy are generally restricted by the formability of sheet metals in the conventional hole-flanging operation. A new hole-flanging process, named upsetting-flanging process, was proposed to ob...Flange height and lip accuracy are generally restricted by the formability of sheet metals in the conventional hole-flanging operation. A new hole-flanging process, named upsetting-flanging process, was proposed to obtain a more substantial flange from thick plate. The finite element method （FEM） with DEFORM was utilized to simulate the novel upsetting-flanging process and the influence of geometric parameters on the flange height was studied in details. A series of flanging experiments with A1050P-O were carried out to validate the FEM results, and the variations of Vicker hardness in the plate section were discussed. The results showed that the newly upsetting-flanging process revealed higher flange height and better lip accuracy than the conventional hole-flanging process, and the results between FEM simulations and experiments showed good agreement. Besides, the hardness of the plate around the flange part increases due to the work hardening after the upsetting-flanging process, which reveals better superiority in strength for the subsequent machining or assembling processes.展开更多
Flange earrings of strong anisotropic sheet metals in deep-drawing process are numerically analyzed by the elastic-plastic large deformation finite element formulation based on a discrete Kirchhoff triangle plate shel...Flange earrings of strong anisotropic sheet metals in deep-drawing process are numerically analyzed by the elastic-plastic large deformation finite element formulation based on a discrete Kirchhoff triangle plate shell element model. A Barlat-Lian anisotropic yield function and a quasi-flow corner theory are used in the present formulation. The numerical results are compared with the experimental ones of cylindrical cup drawing process. The focus of the present researches is on the numerical analysis and the constraining scheme of the flange earring of circular sheets with strong anisotropy in square cup drawing process.展开更多
Jacking force is one of the important safety indicators during pipe jacking construction.Existing models for calculating jacking force are widely used in the calculation of jacking force for pipe with regular cross-se...Jacking force is one of the important safety indicators during pipe jacking construction.Existing models for calculating jacking force are widely used in the calculation of jacking force for pipe with regular cross-sections.In this paper,considering pipe-soil interaction,the cross-sectional characteristics and the distribution characteristics between pipe and soil,the calculation equations for the jacking force of circular steel pipe with flange plate were proposed based on the pressure arch theory.The proposed equations were applied to calculate the jacking force for the Olympic Sports Center Subway Station of Line 9 in Shenyang,China,and the results were compared with the field monitoring data to predict the accurate jacking force.Based on the proposed equations,the influences of the flange plate position and steel pipe diameter on earth pressure around the pipe were analyzed.The functional relationship between the earth pressure and the position of flange plate or the pipe diameter was obtained,which provides design basis and theoretical guidance for engineering practice.展开更多
法兰连接节点抗弯承载性能的研究在国内外几乎是空白,相关的设计方法也不成熟.对4种形式的法兰连接节点,采用通用有限元软件AN SY S,进行了其在弯矩作用下的非线性分析计算.在整体荷载-位移曲线、变形结果和应变结果等三方面,计算结果...法兰连接节点抗弯承载性能的研究在国内外几乎是空白,相关的设计方法也不成熟.对4种形式的法兰连接节点,采用通用有限元软件AN SY S,进行了其在弯矩作用下的非线性分析计算.在整体荷载-位移曲线、变形结果和应变结果等三方面,计算结果均与相应的试验结果吻合良好,验证了有限元模型的可靠性.利用此有限元模型,分析了法兰盘V on-M ises应力和接触应力的发展规律.结果表明:随着荷载的增加,法兰盘表现出了明显的塑性发展特征;在进行法兰连接抗弯设计时,可以认为法兰盘压力中心的位置近似恒定.展开更多
基金Project(51175445)supported by the National Natural Science Foundation of ChinaProject(2010DFA52130)supported by the International Cooperation Project of the Ministry of Science and Technology,ChinaProject(CX2013B277)supported by Hunan Provincial Innovation Foundation for Postgraduate,China
文摘Flange height and lip accuracy are generally restricted by the formability of sheet metals in the conventional hole-flanging operation. A new hole-flanging process, named upsetting-flanging process, was proposed to obtain a more substantial flange from thick plate. The finite element method （FEM） with DEFORM was utilized to simulate the novel upsetting-flanging process and the influence of geometric parameters on the flange height was studied in details. A series of flanging experiments with A1050P-O were carried out to validate the FEM results, and the variations of Vicker hardness in the plate section were discussed. The results showed that the newly upsetting-flanging process revealed higher flange height and better lip accuracy than the conventional hole-flanging process, and the results between FEM simulations and experiments showed good agreement. Besides, the hardness of the plate around the flange part increases due to the work hardening after the upsetting-flanging process, which reveals better superiority in strength for the subsequent machining or assembling processes.
基金The project supported by the National Natural Science Foundation of China (19832020)Provincial Natural Science Foundation of Jilin, China (200000519)
文摘Flange earrings of strong anisotropic sheet metals in deep-drawing process are numerically analyzed by the elastic-plastic large deformation finite element formulation based on a discrete Kirchhoff triangle plate shell element model. A Barlat-Lian anisotropic yield function and a quasi-flow corner theory are used in the present formulation. The numerical results are compared with the experimental ones of cylindrical cup drawing process. The focus of the present researches is on the numerical analysis and the constraining scheme of the flange earring of circular sheets with strong anisotropy in square cup drawing process.
基金supported by the National Natural Science Foundation of China(No.51878127).
文摘Jacking force is one of the important safety indicators during pipe jacking construction.Existing models for calculating jacking force are widely used in the calculation of jacking force for pipe with regular cross-sections.In this paper,considering pipe-soil interaction,the cross-sectional characteristics and the distribution characteristics between pipe and soil,the calculation equations for the jacking force of circular steel pipe with flange plate were proposed based on the pressure arch theory.The proposed equations were applied to calculate the jacking force for the Olympic Sports Center Subway Station of Line 9 in Shenyang,China,and the results were compared with the field monitoring data to predict the accurate jacking force.Based on the proposed equations,the influences of the flange plate position and steel pipe diameter on earth pressure around the pipe were analyzed.The functional relationship between the earth pressure and the position of flange plate or the pipe diameter was obtained,which provides design basis and theoretical guidance for engineering practice.
文摘法兰连接节点抗弯承载性能的研究在国内外几乎是空白,相关的设计方法也不成熟.对4种形式的法兰连接节点,采用通用有限元软件AN SY S,进行了其在弯矩作用下的非线性分析计算.在整体荷载-位移曲线、变形结果和应变结果等三方面,计算结果均与相应的试验结果吻合良好,验证了有限元模型的可靠性.利用此有限元模型,分析了法兰盘V on-M ises应力和接触应力的发展规律.结果表明:随着荷载的增加,法兰盘表现出了明显的塑性发展特征;在进行法兰连接抗弯设计时,可以认为法兰盘压力中心的位置近似恒定.
